1. Field of the Invention
The present invention relates to a magnetic recording head, and more particularly, to a magnetic recording head having a pole structure capable of reducing an antenna effect.
2. Description of the Related Art
Studies on a perpendicular magnetic recording method are being performed to increase a recording density in a magnetic information recording field. In the perpendicular magnetic recording method, magnetization is oriented perpendicular to a disk surface to increase the recording density, unlike in a general longitudinal magnetic recording method.
In the magnetic recording method, wrong information may be recorded in a recording medium or information previously recorded on the recording medium may be erased due to an antenna effect. The antenna effect is a phenomenon where an external magnetic field is introduced into a recording head and an undesired magnetic field concentrates on a specific part of the recording head, for example, on a leading end of the head. Such an external magnetic field is a stray field often generated in an actuator having a magnetic circuit and in a voice coil motor (VCM) for driving the actuator. In the perpendicular recording method that is very sensitive to an external magnetic field because a tip of the head is very small, such an antenna effect may become a serious problem.
Korean Patent Publication No. 10-2002-0041578 discloses a magnetic recording head structured to reduce an antenna effect. The disclosed magnetic recording head includes a magnetic shield layer having a leading end close to a surface of a recording medium. The magnetic shield layer disperses an external magnetic field introduced into the magnetic recording head to prevent the external magnetic field from concentrating on a writing pole and a return pole, thereby reducing an antenna effect. There are other conventional methods that reduce an antenna effect by removing the return pole or separating the writing pole from the return pole.
However, the conventional methods for reducing an antenna effect need to perform a process of forming an antenna effect reducing structure in addition to a head manufacturing process, thereby making the head manufacturing process complex and increasing the manufacturing time and cost thereof.
Furthermore, since the conventional methods only consider the influence of the external magnetic field on a writing part, they cannot reduce an antenna effect generated in a reading part.